Clamp for vulcanizing patches



June 27, 1939. M. E. HILL 2,163,875

CLAMP FOR VULCANIZING PATCHES Filed Jan. l0, 1936 I 3 Sheets-Sheet luni.

Jung 27, 1939. A M. E HILL 2,163,876

CLAMP FOR VULCANIZING PA'ICXIES Filed Jan. l0, 1936 5 Sheets-Sheet 2 INVEN TOR. 7M

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June 27, 1939. M. E. HILL CLAMP `FOR VULCANIZING PATCHES 5 Sheets-Sheet3 Filed Jan* lO, 1936 JNVENToR. 0% s. H BY w MIM/1 TToRNEYS.

Patented June 27, 1939 UNITED STATES PATENT OFFICE Matthew E. Hill,Atlanta, Ga., assignor to The Holfast Rubber Company, Atlanta, Ga., acorporation of Georgia Application January 10, 1936, Serial No. 58,581

8 Claims.

; article to be repaired directly in the line lof pressure exerted bythe clamp, and centering the patch over the injury.

In the repairing of punctures, slits, tears and other injuries to theinner tubes of tires it is highly important that the injury to the tubebe properly centered beneath the position to be occupied by the patchand that the patch be properly centered over such injury. Such patchesas are used for this purpose usually consist of a piece of raw rubberadhesively held on the bottom of a shallow metal pan, the latter beinglled with a suitable combustible which when ignited, provides thenecessary heat for vulcanizing the raw rubber patch over the injury tothe tube. Clamps are used for pressing such pans and patches firmly intocontact'with the tube to be repaired, but as ordinarily constructed nomeans are provided by which the injury can be centered visually, in apractically accurate manner in the clamp and then the pan bemechanilally centered over the injury. The reason for its importancewill be appreciated when it is considered that the shallow pans used areof thin metal, so that upon application of pressure to their rimportions the central part of the patch on the bottom receives lesspressure than the peripheral portions of the patch, whereby the patch iscompressed when heated to lenticular form with a relatively thick centerand a relatively knife-edged periphery. Consequently, if bymiscentering, the injury is positioned beneath the thin peripheralportion of the patch, weakness exists and inflation of the tube resultsin a blowout. In the present invention means are provided whereby theinjury to the tube may be visually centered in the clamp used in suchmanner that the center of pressure effected by the clamp will be centralwith the injury and then the pan with its patch may be applied in suchmanner that the patch will be centered over the injury. By this means,when the operation is completed, the injury will be covered by thethickest portion of the' patch.

One important object of the present invention is to provide an improvedform of such clamp whereby a suitably shaped vulcanizing element may beheld in proper position for vulcanizing a patch centrally over thepuncture or tear in a tube or other article.

Such clamps have also been devised wherein there is either no means orsome special means, separate Vfrom the means for positioning thevulcanizing pans, for holding the tube or other article in position.

A second important object of the present invention is to provide a noveland efficient means for holding the tube or other article in positionduring the vulcanizing operation.

A third important object of the invention is to provide novel resilientmeans to hold the tube or other article in position which will operateeffectively in a manner independent of the size of the tube or otherarticle, and Without respect to irregularities in the thickness of thematerial therein.

A fourth important object of the invention is to provide novel holdingmeans for the tube or other article to be vulcanized which willeffectively hold the same in position in all positions of the movablemember of the clamp.

Apparatus has been devised for the purpose set forth, wherein there isprovided a xed platen designed to support an injured portion of a tubeand a spider movable toward and from this platen to engage the rim of apan such as has been previously mentioned, and to press the patch heldon the bottom of such pan against the injured portion of a tube. In suchapparatus the spider has been carried by a joint having a ball andsocket action on the end of a Screw. With such apparatus it is necessaryto hold the spider against rotation and in proper position to engage therim of the pan. The natural and usual method of doing this is with thefingers of the operator. Since in this type of apparatus the heat fromthe fuel in the pan rises and directly heats the spider, it quicklybecomes diiiicult and inconvenient to adjust the spider to properposition relative to the pan, and danger of burning the lingers of theoperator arises, so that such apparatus is functionally deficient.

A fth important object of the invention is, therefore, to provide animproved form of vulcanizing clamp adapted to have a spider memberengaging the periphery of a pan unit, and wherein the spider member willbe constantly held against rotation, so that at no time will it have tobe manipulated to seat properly on the pan rim.

At the same time it is essential that a clamp for this purpose beprovided with opposed clamping members, one or both of which will betiltable so that independently of the irregularities in the thickness ofthe parts of the tube being repaired, the pressure exerted by suchclamping members will be uniformly distributed substantially around theperiphery of the patch. It is obvious that such a clamp, having a spiderto engage the edge portions of a pan constituting part of thevulcanizing unit and having a platen to support the tube to be repaired,will be imperfect in operation if the spider or upper member be arrangedas a relatively movable member to move toward and from a platen or lowermember, constituting a relatively fixed member, for several reasons. Inthe first place, as above mentioned, such a spider will become too hotto be handled after one or two closely spaced operations as are commonin the operation of devices of this character. In the second place therelatively movable member, and especially the means for moving it, mustbe kept well lubricated. For instance, if the spider which isnecessarily located above the platen, is carried by a ball and socketjoint on the lower end of an adjusting screw extending through the upperpart of the clamp frame, then the lubrication provided for the screw andthe ball and socket joint may either burn out or run and drop onto thetube under repair as soon as the vulcanizing heat is developed.

A sixth object of the present invention is to provide a device of thisclass wherein all parts above the vulcanizing pan are movable so thatthey require neither manual adjustment nor lubrication, and thus, eventhough exposed directly to the vulcanizing heat developed by the fuelburnt in the pan, will not act to interfere with the operation of theinvention.

A seventh important object of the invention is to provide a movableclamp member so arranged that it cannot revolve during its movementtoward and from a relatively stationary clamp member, said movablemember having means carried therewith to hold an article in fixedposition relative to said movable member.

With the above and other objects in view, the invention consists ingeneral of certain novel details of construction and combinations ofparts hereinafter fully described, illustrated in the accompanyingdrawings and specically claimed.

In the accompanying drawings like characters of reference indicate likeparts in the several views, and

Figure 1 is a side elevation of one form of the invention.

Figure 2 is a front elevation thereof.

Figure 3 is a section on the line 3-3 of Figure 1.

Figure 4 is a detail section on the line 4-4 of Figure l.

Figure 5 is a detail section on the line 5 5 of Figure 2.

Figure 6 is a detail section on the line 6 6 of Figure 1.

Figure 7 is a side elevation of a modified form of the invention.

Figure 8 is a section on the line 8-8 of Figure 7.

In both forms of the embodiments of the invention as herein disclosedthere is provided a substantially C-shaped frame having an upper arm I6and a lower arm II, the major part of the frame being I-shaped in crosssection. At the back or vertical portion I2 of this frame, in the formshown in Figures l and 2, there is pro'- vided a pair of laterallyextending wings I3 provided with bolt or screw openings I4 S0 that theframe may be secured by suitable bolts or screws to any desired support.Extending forwardly from the vertical portion of the frame is a rib I5,the purpose of which will presently be described. It is, however, to beunderstood that this rib simply constitutes a vertical guide and mayhave any other equivalent guide means substituted therefor.

At the forward end of the upper arm IIJ is a boss I6 to which is xed aspider I'I` having outwardly extending and downwardly curved arms havingat under surfaces or feet I8. The lower arm I I is similarly provided atits extremity with a boss I9. In the form shown in Figures 1 and 2 thisboss has an internally threaded opening wherethrough extends a screw 20provided at its lower end with manually operable means 2I by which thescrew may be rotated, and thus caused to travel toward and from thespider, the screw being axially alined with the center of said spider.

In the form of the invention shown in Figure '7 the boss I9 is replacedby a cylindrically apertured boss I9a wherethrough passes a slidableplunger 20a and below the boss I9a the stern or plunger 26a has pivotedthereto a cam lever 2Ia which has a cam end 2Ib engaging the under sideof the boss I9a, so that upon the handle end of the boss 2Ia beingpulled downwardly, the stem or plunger 20a moves downwardly through theboss I9a.

Between the arms I0 and I I is located a platen or platform 22 which isprovided on its under side with a boss 23 provided with a recess 24which extends upwardly from its lower face. In this recess loosely tsthe upper end of the screw 26 or the plunger 26a as the case may be,each of which is provided at this upper end with a peripheral groove 25wherein seats the end of a screw 26 inserted through a suitable threadedopening 21.

This screw engages in the groove 25 and thus holds the platen to movewith the screw 20 or plunger 26a, as the case may be. On the upper endof the screw 20 or plunger 20a is positioned a hardened steel bearingball 26 which forms a support for the platen. Obviously, this ball 26may be omitted if desired, and this is especially true of the form ofthe invention shown in Figure '7.

In the form shown in Figure '7 a spring 21a between the boss I9a and theboss 23 urges the t platen up towards the spider.

At the rear edge of the platen 22 in each form is a forked extension 29the arms of which straddle the rib I5 or other guide means, so that theplaten is held from rotation as it is moved up and down by the screw.

On top of the platen 22 is located a loop of spring wire, which is shownin Figure 3 as having a front arcuate lobe 30 and lateral oppositelydisposed lobes 3| which latter are of such size a sleeve 35 surroundingthe parallel portion 36 f of the wire above the platen 22. From the rearof the flanges 35 the wire ends extend down around the rear side edgesof the platen 22 and forwardly to the sides of the boss Where they aresecured by screws 3l. By means of this arrangement the loop formed bythe lobes 30 and 3l is urged constantly againstthe upper surface of theplaten 22.

This loop may have an alternative form to accommodate rectangular pans,the form being such as is shown in Figure 8 at 38. Obviously, the loopmay be of any other desired form but it is not deemed necessary nordesirable to here show all forms in which lthis loop may be made. In allcases, however, it will be obvious that the injury to any-tube, when thelatter is placed on the platen beneath the loop, may be positioned byeye with very close approximation to the center of the loop, and sincethe loop is in all cases formed to center the pan, after the injury hasbeen centered, the pan will by its positioning in the loop,automatically center the patch over the injury.

In use the tube to be vulcanized is placed on the platen beneath thespring clamp in such position that the puncture or tear is centered asat A in Figure 3 by eye in the center of the loop, the spring clamp orloop serving to retain the article in this position during the remainderof the operation. Next, depending on the size and shape of the punctureor tear, a suitable vulcanizing unit consisting of a pan having fueltherein and a patch on its underside is positioned in the wire loopforming the clamping spring. Obviously, the vulcanizing units will beheld in position by the wire loop, but if it is desired to use a smallerunit than the loop 33, the latter may be manually held but will becentered by eye in the loop. The screw or plunger is then manipulateduntil the platen is raised to such position that the spider engages thepan and presses the patch rrnly on the article being repaired. Next thefuel in the pan is ignited and the patch is vulcanized in position inthe usual manner. Finally the screw or plunger is loosened and thepatched article withdrawn.

There has thus been provided a simple and efficient device of the kinddescribed and for the purpose specied.

It is obvious that changes may be made in the form and proportions ofthe device without departing from the spirit of the invention. It isnot, therefore, desired to conne the invention to the exact form hereinshown and described, but it is desired to include all such as comewithin the scope of the appended claims.

What is claimed is:

1. A vulcanizing clamp including a frame having an upper and a lowerarm, a clamping screw threaded through said lower arm and projectingupwardly therefrom, a platen loosely mounted on the upper end of saidscrew so that the screw can turn while the platen does not, a spidercarried by said upper arm and having arms extending over said platen,and a spring member attached to said platen and extending thereover togrip an article onto the platen during vulcanization said spring havinga loop of proper size and shape to receive and closely fit aroundperipheral portions of the standard shapes of the pans of vulcanizingunits.

2. A vulcanizing clamp including a frame having an upper and a lowerarm, pressure means extending through said lower arm and projectingupwardly therefrom, a platen mounted on the upper end of said pressuremeans, means for holding said platen against rotation relatively to thesaid frame, a spider carried by said upper arm and having arms extendingover said platen, and a spring clamp attached'to said platen andextending thereover to"`fgrip an article to be vulcanized onto theplaten,y said spring clamp having a space within its periphery soconstructed and arranged as to receive and position a freely movablevulcanizing unit, and having a shape conforming with the shape of thecommon vulcanizing units.,V t t 3. A vulcanizing clamp including a framehaving an upper and a lower arm, pressure means extending through saidlower arm and projecting upwardly therefrom, a'platen mounted on theupper end of said pressure means, a spider carried by said upper arm andhaving arms extending over said platen, and a spring clamp attached tosaid platen and extending thereover to grip an article to be vulcanizedonto the platen, said spring clamp being formed of wire and having anopen loop extending over the upper surface of said platen said springhaving a loop of proper size and shape to receive and closely :litaround peripheral portions of the standard shapes of the pans ofvulcanizing units.

4. A vulcanizing clamp including a frame having an upper arm and a lowerarm, a clamping screw threaded through said lower arm and projectingupwardly therefrom, a platen mounted on the upper end of said screw,rotation of said screw causing a raising and lowering of said platen, aspider carried by said upper arm and having arms extending over saidplaten, and a spring clamp attached to said platen and extendingthereover to grip a freely movable vulcanizing unit having a patch onits bottom to be vulcanized onto the platen, said spring clamp beingformed of wire and having an open loop extending over the upper surfaceof said platen, and provided with oppositely disposed lobes adapted toreceive peripheral portions of the vulcanizing unit to position thelatter.

5. A vulcanizing clamp including a frame having an upper and a lowerarm, a clamping screw threaded through said lower arm and projectingupwardly therefrom, a platen loosely mounted on the upper end of saidscrew, a spider carried by said upper arm and having arms extending oversaid platen, a spring clamp attached to said platen and extendingthereover to grip an article to be vulcanized onto the platen, and meansto prevent rotation of said platen during its actuation by the screw,said spring clamp being of a size and shape to position either thecommon round or oval vulcanizing units.

6. A vulcanizing clamp including a frame having an upper and a lowerarm, a clamping screw threaded through said lower arm and projectingupwardly therefrom, a platen loosely mounted on the upper end of saidscrew, a spider carried by said upper arm and having arms extending oversaid platen, a spring clamp attached to said platen and extendingthereover to grip an article to be vulcanized onto the platen, saidspring clamp having a space within its periphery so constructed andarranged as to receive and position a vulcanizing unit, a guide on saidframe extending vertically thereof, and means on the platen slidablyengaging the guide to hold the platen against rotation as it is movedupwardly and downwardly by said screw.

'7. A vulcanizer including a frame having opposing members, one of saidmembers carrying immovable arms for engaging a pan adapted to contain acombustible medium, the other member carrying a vertically movableplaten which is loosely mounted thereon, said platen having attachedthereto a clamp which extends thereis loosely mounted thereon, and whichplaten is provided with means for adjustably raising and lowering thesame, said platen having attached thereto a clamp which extendsthereover to grip an article which is to be vulcanized, said clamphaving a space within its periphery, said space within the periphery ofthe clamp being shaped to receive and position vulcanizing units of aplurality of sizes and shapes.

MATTHEW E. HILL.

